Association of outdoor air pollution with the medical expense of ischemic stroke: The case study of an industrial city in western China.

ABSTRACT

Ischemic stroke, the most frequent cause of severe disability, imposes a significant mental and economic burden on patients and their families. There is increasing evidence to indicate that air pollution contributes to the risk of ischemic stroke. This study aimed to examine the correlation between air pollution and the expense imposed by an ischemic stroke. Data were obtained from hospitals and environmental monitoring stations in an industry city, Longspring, in western China. We used a generalized additive model to estimate the associations between the two factors, measured during 2015-2017. Counter-intuitively, the medical expenses arising from ischemia were negatively associated with the level of air pollution. The corresponding ER for per interquartile range increase of PM2.5, PM10, SO2 , and NO2 in lag10 was -0.17% (95% confidence interval (95% CI -0.31%, -0.03%), -0.11% (95% CI -0.2%, -0.02%), -1.04% (95% CI -1.92%, -0.17%) and -0.44% (95% CI -0.66%, -0.22%), respectively (p < 0.05). Subgroups based on gender, age, and season were considered in the analysis. The results indicated that pollutants had significant effects on ischaemia's medical expenses, which were stronger for older people, patients who survived, and warm seasons. This study is the first step in optimizing medical resources, which are essential for policymaking and service planning.